44

I have a RecyclerView which is a vertical scrolling list of items. Each list item contains a Google Maps V2 MapView in Lite Mode. I'm taking advantage of this new feature which returns bitmaps instead of a full-blown map as a replacement to the Google Static Maps API.

MapView requires that you call onCreate(), onResume(), onPause(), onDestroy() etc. from the parent Activity/Fragment's corresponding method. Where is the proper place to call these from the RecyclerView.Adapter and/or RecyclerView.ViewHolder?

How can I clean up recycled MapViews so that memory doesn't leak, while keeping the list jank free?

Google says Lite Mode can be used in lists:

... ‘lite mode’ map option, ideal for situations where you want to provide a number of smaller maps, or a map that is so small that meaningful interaction is impractical, such as a thumbnail in a list.

ListItem.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
                android:layout_width="fill_parent"
                android:layout_height="fill_parent">

    <com.google.android.gms.maps.MapView
        android:id="@+id/mapImageView"
        xmlns:map="http://schemas.android.com/apk/res-auto"
        android:layout_width="80dp"
        android:layout_height="100dp"
        map:liteMode="true"
        map:mapType="normal"
        map:cameraZoom="15"/>

<!-- ... -->

</RelativeLayout>

RecyclerView.Adapter and ViewHolder

public class NearbyStopsAdapter extends RecyclerView.Adapter<NearbyStopsAdapter.ViewHolder> {

    private final Context mContext;

    public class ViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {

        MapView map;

        public ViewHolder(View view) {
            super(view);
            map = (MapView) view.findViewById(R.id.mapImageView);
            // Should this be created here?
            map.onCreate(null);
            map.onResume();
        }
    }

    public NearbyStopsAdapter(Context c) {
        this.mContext = c;
    }

    @Override public ViewHolder onCreateViewHolder(ViewGroup viewGroup, int position) {
        View itemView = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.list_item_nearby_stop, viewGroup, false);
        return new ViewHolder(itemView);
    }

    @Override public void onBindViewHolder(ViewHolder holder, int position) {
        //Call Async Map here?
        holder.map.getMapAsync(this);
    }

    @Override public void onViewRecycled(ViewHolder holder) {
        // Cleanup MapView here?
//        if (holder.map != null) {
//            holder.map.onPause();
//            holder.map.onDestroy();
//        }
    }

    @Override public void onViewAttachedToWindow(ViewHolder holder) {
        // Setup MapView here?
//            holder.map.onCreate(null);
//            holder.map.onResume();
    }

    @Override public void onViewDetachedFromWindow(ViewHolder holder) {
        // Cleanup MapView here?
//        if (holder.map != null) {
//            holder.map.onPause();
//            holder.map.onDestroy();
//        }
    }

    // ...
}

Logcat:

I/Google Maps Android API﹕ Google Play services package version: 659943
W/Google Maps Android API﹕ Map Loaded callback is not supported in Lite Mode
W/Google Maps Android API﹕ Buildings are not supported in Lite Mode
W/Google Maps Android API﹕ Indoor is not supported in Lite Mode
W/Google Maps Android API﹕ Toggling gestures is not supported in Lite Mode
W/Google Maps Android API﹕ Toggling gestures is not supported in Lite Mode
W/Google Maps Android API﹕ Toggling gestures is not supported in Lite Mode
W/Google Maps Android API﹕ Toggling gestures is not supported in Lite Mode

Update: (Jun 8, 2018) Google has released a code sample for using Lite Maps in a ListView. See here

4
  • Is this question about your RecyclerView not behaving smooth or garbage collection of a MapView? I don't think these two problems are tightly connected. Commented Feb 25, 2015 at 8:48
  • The jank occurs when calling getMapAsync(this) in onBindViewHolder(...), not necessarily on a GC. Though, there will be jank there too.
    – Ryan R
    Commented Mar 2, 2015 at 4:05
  • Moving mapView.onCreate(null); and mapView.getMapAsync(this); from onBindViewHolder to the ViewHolder constructor definitely reduced a bunch of jank for me.
    – scottyab
    Commented Aug 26, 2016 at 14:09
  • 1
    the link you provided has expired, here's the new one, definitely useful and should solve the probelm: github.com/googlemaps/android-samples/blob/master/ApiDemos/java/… Commented Jun 8, 2018 at 10:27

6 Answers 6

30

Solution as following:

  1. Implement OnMapReadyCallback in ViewHolder class.
  2. In onMapReady, call MapsInitializer.initialize, to gaurantee features can to be used before obtaining a map.

Use this class to initialize the Google Maps Android API if features need to be used before obtaining a map. It must be called because some classes such as BitmapDescriptorFactory and CameraUpdateFactory need to be initialized.

  1. Recycle map from onViewRecycled.


    public class NearbyStopsAdapter extends RecyclerView.Adapter<NearbyStopsAdapter.ViewHolder> {


       @Override 
       public void onBindViewHolder(ViewHolder holder, int position)  
       {
          //get 'location' by 'position' from data list
          //get GoogleMap
          GoogleMap thisMap = holder.gMap;
          //then move map to 'location'
          if(thisMap != null) 
             //move map to the 'location' 
             thisMap.moveCamera(...);          
       }


       //Recycling GoogleMap for list item
       @Override 
       public void onViewRecycled(ViewHolder holder) 
       {
          // Cleanup MapView here?
          if (holder.gMap != null) 
          {
              holder.gMap.clear();
              holder.gMap.setMapType(GoogleMap.MAP_TYPE_NONE);
          }
       }



       public class ViewHolder extends RecyclerView.ViewHolder implements OnMapReadyCallback { 

           GoogleMap gMap; 
           MapView map;
            ... ... 

           public ViewHolder(View view) {
              super(view);
              map = (MapView) view.findViewById(R.id.mapImageView);

              if (map != null) 
              {
                 map.onCreate(null);
                 map.onResume();
                 map.getMapAsync(this);
              }

          }


          @Override
          public void onMapReady(GoogleMap googleMap) {
              //initialize the Google Maps Android API if features need to be used before obtaining a map 
              MapsInitializer.initialize(getApplicationContext());
              gMap = googleMap;

              //you can move map here to item specific 'location'
              int pos = getPosition();
              //get 'location' by 'pos' from data list  
              //then move to 'location'
              gMap.moveCamera(...);

                  ... ...
         }

       }
    } 
7
  • Let us continue this discussion in chat.
    – Ryan R
    Commented Mar 2, 2015 at 17:07
  • MapView is not the same as GoogleMap. You cannot do map = googleMap; in onMapReady(...)
    – Ryan R
    Commented Mar 2, 2015 at 19:51
  • This is getting closer, though there is the case when the list is first loaded holder.gMap can be null in onBindViewHolder(...). The user would have to move the list to "refresh" the item.
    – Ryan R
    Commented Mar 3, 2015 at 17:32
  • 1
    For this case, if you do not want null, then in your XML, the MapView should have a dumy img/bmp , perhaps this is only solution because we can not control the process.
    – Xcihnegn
    Commented Mar 3, 2015 at 17:39
  • 2
    Here is my adapter, it's works pretty nice, maybe it would be usefull for you:gist.github.com/Yazon2006/5d7fd1716093441e3b25e088f9332cf8
    – Yazon2006
    Commented Jun 16, 2016 at 8:33
5

Google says:

When using the API in fully interactive mode, users of the MapView class must forward all the activity life cycle methods to the corresponding methods in the MapView class. Examples of the life cycle methods include onCreate(), onDestroy(), onResume(), and onPause().

When using the MapView class in lite mode, forwarding lifecycle events is optional, except for the following situations:

It is mandatory to call onCreate(), otherwise no map will appear. If you wish to show the My Location dot on your lite mode map and use the default location source, you will need to call onResume() and onPause(), because the location source will only update between these calls. If you use your own location source, it's not necessary to call these two methods.

So on lite mode you don't have to worry about onDestroy(), onResume() and onPause()

3

Find Google Maps Android API Lite Mode Example (source code)

Google Map Lite - github.com

1
  • googlemap v1 will be remove soon, as you can see when publish app to store then u will get this message
    – famfamfam
    Commented Dec 29, 2021 at 6:57
3

Google map provides Lite Mode

The Maps SDK for Android can serve a bitmap image of a map, offering limited interactivity to the user. This is called a lite mode map.

Lite Mode

Follow the LiteListDemoActivity: Displaying maps efficiently in ListViews using lite mode example.

0

You need to have a separate View Holder class. The RecyclerView Adapter class will just have onCreateViewHolder() and onBindViewHolder().

Your Layout file should look something similar to this:

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    android:paddingBottom="@dimen/activity_vertical_margin"
    tools:context=".MyActivity">

    <view
    <com.google.android.gms.maps.MapView
    android:id="@+id/mapImageView"
    xmlns:map="http://schemas.android.com/apk/res-auto"
    android:layout_width="80dp"
    android:layout_height="100dp"
    map:liteMode="true"
    map:mapType="normal"
    map:cameraZoom="15" />

</RelativeLayout>

And the onCreate(), onDestroy() will be called in the Activity class as usual.

Please follow this tutorial to get a complete overview.

5
  • 1
    I think you might have missed the question. There is already a ViewHolder defined in the RecyclerView.Adapter. The question is where should MapView.onCreate(), MapView.onDestroy() etc. be called?
    – Ryan R
    Commented Feb 19, 2015 at 20:05
  • Please see the line just below the layout file code "And the onCreate(), onDestroy() will be called in the Activity class as usual."
    – AniV
    Commented Feb 19, 2015 at 20:56
  • Your link does not include a MapView. How is it relevant?
    – Ryan R
    Commented Feb 19, 2015 at 23:11
  • It is the usual Activity class... With onCreate() and rest of Android lifecycles methods described. For more details see this code that has mapView in Franment and data pulled from layout inflater gist.github.com/joshdholtz/4522551
    – AniV
    Commented Feb 19, 2015 at 23:18
  • 1
    The RecyclerView does not have onCreate() and the rest of the Android lifecycle methods. And the RecyclerView contains many list items which each contain a MapView, which is recycled when the user scrolls the list. As a result the MapView for each item has to be created and destroyed. The question is where to call the MapView.onCreate(), etc. from within the RecyclerView not the Fragment or Activity.
    – Ryan R
    Commented Feb 19, 2015 at 23:29
0

I have removed this Override method because every time this gives empty map when testing and it works perfectly in my recyclerView.

@Override 
public void onViewRecycled(ViewHolder holder) 
{
  // Cleanup MapView here?
  if (holder.gMap != null) 
  {
      holder.gMap.clear();
      holder.gMap.setMapType(GoogleMap.MAP_TYPE_NONE);
  }
}

You can try it if above code does not work in your case as well.

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